Abstract

The thermal expansion of AI-10.3U, AI-16.2U, AI-22U, AI-8.1U-1Zr, AI-16.2U-1Zr, AI-22U-2Zr, AI-30U-2Zr and A1-46U-3Zr alloys (all compositions are in wt%) were measured from room temperature to $550^oC$ using a high temperature dilatometer. The coefficient of thermal expansion (CTE) was found to increase with temperature for AI-8.1U-1Zr and AI-10.3U alloys while for higher uranium containing ternary alloys namely AI-30U-2Zr and AI-46U-3Zr the CTE decreased with temperature. The CTE of AI-U and AI-U-Zr alloys generally decreased with increase in uranium content. The differences in the thermal expansion behaviour of these binary and ternary alloys have been attributed to their microstructures and the amount of $UAI_3$, $UAI_4$ and AI in these alloys.